SS-8 Sasin
The R-9 (NATO reporting name: SS-8 Sasin) was a two-stage ICBM of the Soviet Union, in service from 1964 to 1976.
History
Designed in 1959 and first tested in 1961, the R-9 was a great improvement over previous Soviet missile designs. The missile, capable of delivering a 3,500 lb (1600 kg) payload about 6,000 nautical miles (11,000 km) to an accuracy of 1 nautical mile (2 km), was not only very accurate, but was also far more tactically useful to the Soviet Union. Previous Soviet designs, fuelled with cryogenic LOX and kerosene, commonly took hours to fuel and launch. The R-9, on the other hand, could be launched 20 minutes from the time a launch order was given. The missile's control system was designed by NPO "Electropribor" (Kharkiv, Ukraine).
First put into active service in 1964, the R-9 carried a 1.65 to 5 Mt warhead. Though the last Soviet missile to use cryogenic propellant, this design is one of the most widely deployed ICBMs to use cryogenic fuel. The initial stage of the two-stage missile was a four-chambered closed cycle design developed by OKB-456 (later renamed to NPO Energomash). The second stage, connected by trusses to the first stage (much like the modern Soyuz rocket) was also four-chambered, but utilized open combustion chambers more suited to very high altitudes. This rocket engine was a product of the OKB-154 design team. Guidance of the warhead, like most ICBMs before and after it, was totally inertial save the final ten seconds before detonation of the warhead, which was controlled by a radio-altimeter correction system.
